Fluid jet PMR

ABSTRACT

Devices and methods for performing myocardial revascularization using fluid jets. Devices can include a pressurized fluid source coupled through fluid supply lumens to a distal-most nozzle disposed on the distal end of the catheter. Some devices have separate myocardial revascularization catheters disposed within guide catheters, while other devices have unitary devices including a generally steerable myocardial revascularization catheter shaft. Preferred embodiments include a distally disposed control valve. One valve is controlled using an electrically actuated device, another valve is controlled using a low-pressure control fluid, while yet another device valve is controlled using an axially slidable activation wire. The fluid valve can include a biasing spring to shut the valve and preclude fluid flow, with the bias opposed by a user-applied fluid, mechanical, or electrical force. One device includes a radially expandable distal catheter portion, which expands under pressure to present a significantly larger distal profile. The inflated distal region may be forced against a heart chamber wall, and can provide a larger surface area and improved seal. One catheter includes an intermediate expandable tubular anchor portion. Fluid used in the devices can include saline, revascularization enhancing therapeutic substances, angiogenic promoting substances, and radiopaque contrast media, all of which can be injected at the same time.

FIELD OF THE INVENTION

[0001] The present invention is related generally to medical devices.More specifically, the present invention includes devices for performingmyovascular revascularization including percutaneous myocardialrevascularization (PMR).

BACKGROUND OF THE INVENTION

[0002] A number of techniques are available for treating cardiovasculardisease, such as cardiovascular bypass surgery, coronary angioplasty,laser angioplasty and atherectomy. These techniques are generallyapplied to bypass or open lesions in coronary vessels to restore andincrease blood flow to the heart muscle. In some patients, the number oflesions is so great, or the location so remote in the patientvasculature, that restoring blood flow to the heart muscle is difficult.Percutaneous myocardial revascularization (PMR) has been developed as analternative to these techniques which are directed at bypassing orremoving lesions. PMR is performed by boring holes directly into themyocardium of the heart.

[0003] PMR was inspired in part by observations that reptilian heartmuscle is supplied primarily by blood perfusing directly from withinheart chambers to the heart muscle. This contrasts with the human heartwhich is supplied by coronary vessels receiving blood from the aorta.Positive results have been demonstrated in some human patients receivingPMR treatments. These results are believed to be caused in part by bloodflowing from within a heart chamber through patent holes formed by PMRto the myocardial tissue. Suitable PMR holes have been proposed to beburned by laser, cut by mechanical means, and burned by radio frequencydevices. Increased blood flow to the myocardium is also believed to becaused in part by the healing response to wound formation, specifically,the formation of new blood vessels in response to the newly createdwound.

[0004] What would be desirable are improved methods and devices forperforming myocardial revascularization. In particular, methods allowingsimultaneous hole formation in the myocardium and injection of contrastmedia would be advantageous. Improved methods for stabilizing myocardialrevascularization catheters during use would also be desirable.

SUMMARY OF THE INVENTION

[0005] The present invention includes catheters for forming holes in themyocardium of a heart chamber wall. One catheter has a distal region, aproximal region, and an elongate tubular shaft having a lumentherethrough. A distal nozzle in fluid communication with the lumen canbe disposed at the distal-most region of the catheter shaft. A fluidcontrol valve can be disposed somewhere along the catheter shaft lengthfor controlling fluid flow through the fluid lumen. The fluid flowthrough the valve can be controlled using varying devices in the variouscatheters.

[0006] One device includes electrical means for actuating the fluidcontrol valve. In another device, the valve includes a biasing spring tobias the valve in a closed position, with the opening force beingprovided by an electrically actuated member acting to oppose the biasingspring. In one device, the electronic actuating member is a Nitinolmember heated by current passing from one end to the other end throughthe member. In this embodiment, heating a Nitinol wire shortens thewire, which opens the valve to fluid flow. In another embodiment, a flowor control pressure lumen is provided through the catheter, with thecontrol pressure used to open and shut the valve, thereby allowing thehigh pressured jet fluid to flow through the valve. In one embodiment, aneedle valve is used which includes a valve stem seated within a valveseat, where the valve stem can be retracted proximally to allow flowthrough the valve seat. In yet another embodiment, a mechanicalactuating wire is used to open the control valve. In one embodiment, anelongate control wire is operably coupled to a distal valve stem. Thevalve stem can have a first position for occluding flow through a valveseat, and a second position for allowing flow through the valve seat. Inone device, the actuation wire is proximally retracted to allow flow,and distally extended to preclude flow. In another embodiment, a biasingspring is included within the distal region, acting to shut the valve inthe absence of any applied mechanical force. In this embodiment, theactuation wire can be retracted to open the valve to fluid flow. In oneembodiment, the retractable activation wire may be sufficiently strongunder tension, but not compression, to open the valve.

[0007] The control valve can be located at any position along thecatheter shaft length, with a preferred embodiment having a distallydisposed control valve. The distally disposed control valve can allowfor a relatively large inside diameter distal accumulator and orifice,while having a substantially smaller cross-section supply lumenextending the length of the catheter. This allows for a slow pressurebuildup in the distal region of the catheter, followed by rapidinjection of high pressure fluid into the heart wall.

[0008] One catheter includes preferentially expandable regions whichexpand more readily than other regions under pressure. In one example, afar distal region of a catheter device is formed of a more pliant, moreeasily expandable tube wall material. The more readily expanded materialmay inflate and expand radially under pressure. In one device, thedistal-most region of the catheter is formed of a readily inflatablematerial. In use, the catheter formed of the more readily inflatedmaterial may be inflated to significantly increase the distalcross-sectional area of the catheter, whereupon the increasedcross-sectional distal tip is forced against the heart chamber wall, forimproving the seal against the heart wall. One catheter according to thepresent invention includes an intermediate region which is also morereadily expandable than the immediate more proximal and distal regions.The expandable intermediate region can serve to anchor the fluid jetcatheter within an enclosing guide catheter. The anchored catheter canmore easily withstand pressures or forces which could otherwise act toshift the position of the fluid jet catheter.

[0009] Fluids which are used in the present invention can includerelatively inert fluids such as saline, suitable therapeutic substances,angiogenic enhancing substances, as well as radiopaque contrast media.Adhesive agents can also be included for enhancing the retention oftherapeutic substances within the heart wall. The inclusion ofradiopaque contrast media allows holes to be formed and contrast mediato be injected in a single step. The contrast media allows the alreadytreated regions to be visualized under fluoroscopy by the treatingphysician.

BRIEF DESCRIPTION OF THE DRAWINGS

[0010]FIG. 1 is a perspective, cut-away view of a fluid jet PMR catheterdisposed within a guide catheter, forming holes in the left ventriclemyocardium;

[0011]FIG. 2A is a highly diagrammatic plan view of a fluid jet PMRsystem;

[0012]FIG. 2B is a transverse, cross-sectional view of the fluid jet PMRcatheter of FIG. 2A;

[0013]FIG. 3 is a fragmentary, cut-away, longitudinal, cross-sectionalview of a fluid jet PMR catheter distal region having a biasing springand an electrically activated opening mechanism;

[0014]FIG. 4 is a fragmentary, longitudinal, cross-sectional view of afluid jet PMR catheter distal region having a fluid controlled valve;

[0015]FIG. 5 is a highly diagrammatic, plan view of a fluid jet PMRcatheter system having a wire-activated distal valve;

[0016]FIG. 6 is a fragmentary, longitudinal, cross-sectional view of afluid jet PMR catheter distal region having a spherical valve stemseated against a valve seat portion of a nozzle and controlled by anelongate wire valve control member;

[0017]FIG. 7 is a fragmentary, longitudinal, cross-sectional view of thecatheter of FIG. 6, shown in an expanded state;

[0018]FIG. 8 is an end view of the catheter of FIG. 7, in the expandedstate; and

[0019]FIG. 9 is a highly diagrammatic, side view of a fluid jet PMRcatheter having an expandable intermediate portion for stabilizing thecatheter within a guide catheter.

DETAILED DESCRIPTION OF THE INVENTION

[0020]FIG. 1 illustrates a heart 20 having a guide catheter 22 disposedwithin an aorta 24 and extending into a left ventricle 26. Guidecatheter 22 is preferably a steerable catheter and can serve to containa fluid jet PMR catheter 28 having a distal tip 29 disposed within.Fluid jet PMR distal tip 29 is shown after a plurality of channels 30have been formed within myocardium 32. In a preferred system and methodof using the present invention, fluid jet PMR catheter 28 is disposedwithin a guide-in-guide catheter, or tube-within-steerable-tube,catheter. For example, see U.S. Pat. No. 5,968,059 to Ellis et al.,entitled TRANSMYOCARDIAL REVASCULARIZATION CATHETER AND METHOD; and U.S.Pat. No. 6,056,743 to Ellis et al., entitled PERCUTANEOUS MYOCARDIALREVASCULARIZATION DEVICE AND METHOD, herein incorporated by reference.

[0021]FIG. 2A illustrates a fluid jet PMR system 40 having a steerablecatheter 42, which can be a guide catheter, coupled to a pressure source44, and having a fluid jet PMR catheter 46 disposed within. Fluid jetPMR catheter 46 can terminate in a distal nozzle 47. Fluid jet system 40includes a pressure regulator 48 for regulating pressure from pressuresource or canister 44, and is coupled to a pressure supply line 50,which is in turn coupled to a pressure manifold port 52. Pressuremanifold port 52 is in fluid communication with fluid jet distal nozzle47. In the embodiment illustrated in FIG. 2A, fluid jet catheter system40 includes a proximal region 54 and a distal region 56 on steerablecatheter 42. In the embodiment shown, proximal region 54 is coupled to aproximal control assembly 58 which, in the embodiment shown, is anelectrical control assembly. Proximal control assembly 58 can include anactivation button 60, a safety button 62, a steering handle 64, a powersupply cord 66, and a electrical plug 67. Also illustrated is a battery68, coupled through a power cord 70, to an electrical plug 72, forjoining to plug 67. Proximal control assembly 58, in the embodimentillustrated in FIG. 2A, provides electrical control signals forcontrolling a distal valve coupled to distal nozzle 47.

[0022] Referring now to FIG. 2B, catheter 42 is shown in a transversecross-section. Catheter 42 can include a shaft or body 43 including asteering pull wire 78 slidably disposed therein. A pair of electrodewires 80 can also be disposed within shaft 43 to provide electricalsignals to distal nozzle 47. A pressure fluid lumen 76 is alsoillustrated, being defined within a pressure tube 74 in the illustratedembodiment. In one device, pressure lumen 76 is defined within a metaltube, which can be formed of Nitinol. In another embodiment, lumen 76 isdefined within shaft 43, not requiring a separate tube. In anotherembodiment, not requiring illustration, electrical wire pair 80 can bereplaced or supplanted by a fluid control lumen which can be defined bya fluid control tube. In one embodiment, steerable catheter 42 includesa catheter shaft disposed within a steerable guide catheter such as aguide-in-guide catheter. In this embodiment, a steering pull wire can beprovided within the guide catheter, rather than within the fluid jet PMRcatheter shaft itself.

[0023] Referring now to FIG. 3, a pressure jet PMR catheter 100 isillustrated, having an intermediate region 106, a distal region 102, anda distal tip 104. Pressure jet device 100 includes an outer sleeve orguide catheter portion 103, a pull wire 101, and a pressure supply lumen108 disposed therein. A valve assembly 110 is disposed in distal region102, and includes a fixed block 112, coupled to a spring or biasingmechanism 114, also coupled to an electrically actuated control element116. Biasing spring 114 and control element 116 can both be coupled to aneedle valve body 118 which rests in a fixed Block 120 having a lumen121 therethrough for receiving the needle valve body. Needle valve body118 can extend distally into a valve stem portion 122 which isillustrated lying within a fluid reservoir portion 129 and also residingwithin and against a valve seat portion 124, with valve stem 122occluding a fluid flow lumen 125 disposed within valve assembly 110. Anozzle portion 126 is illustrated, extending distally to a distal-mostorifice 132 within distal tip 104. Fluid, under pressure, may be seen toflow through pressure lumen 108, through a pressure fluid intermediateregion 128, and into fluid reservoir 129. When valve stem 122 isdisposed sufficiently proximal of valve seat 124, fluid flows throughlumen 125, and out of orifice 132 as a fluid jet 130.

[0024] As can be seen from inspection of FIG. 3, spring 114 acts to biasvalve stem 122 in the distal and closed position. Electronic controlmember or element 116, when activated, can act to retract valve stem 122from valve seat 124. In one embodiment, control element 116 includes atemperature sensitive, shape memory member. Electrical control element116 can be supplied by a pair of electrodes 134, with one embodimenthaving an electrode electrically coupled to opposite ends of the controlelement. In one embodiment, when electrical potential is applied acrossthe electrical control member, current flows through the controlelement, thereby raising the temperature, thereby changing the shape ofthe control element. In one example of the invention, electrical currentis passed through a Nitinol wire, which heats and shortens the wire,thereby retracting or shortening control element 116 and retractingvalve stem 122. When current is removed, control element 116 canlengthen, thereby shutting valve assembly 110 and precluding fluid flowthrough the valve. While one embodiment of the invention uses atemperature sensitive element which changes dimensions upon applicationof electrical potential, other electrically activated devices would beapparent to those skilled in the art. In another embodiment of theinvention, not requiring illustration, the biasing spring can bias thevalve in the open position, with the control member acting to stop flowthrough the valve.

[0025] In some embodiments, a high pressure fluid within pressure lumen108 can act to force valve stem 122 proximally out of valve seat 124. Inthese embodiments, a sufficiently strong biasing spring is used so as tocounteract this force. Needle valve 118 can also be dimensioned suitablyto provide a small surface area upon which the high pressure can act,thereby reducing the tendency of the pressure fluid to unseat the valvestem until such time as fluid flow is desired by the treating physician.

[0026] Referring now to FIG. 4, another fluid jet PMR device 200 isillustrated. Fluid jet device 200 includes and shares many features offluid jet device 100 illustrated in FIG. 3. Like numbered elements ofFIG. 3 that are repeated in FIG. 4 are so identified and need not bediscussed further. Fluid jet PMR device 200 includes generally acatheter shaft 200 having a lower pressure fluid lumen 204 disposedwithin. Lower pressure lumen 204 is in fluid communication with a fluidaccumulator portion 206 within the valve body. Fluid accumulator portion206 is in communication with, and brings pressure to bear upon, a valvebody face region 208.

[0027] When sufficiently high control pressure is introduced into lowerpressure lumen 204, pressure is brought to bear on valve body 118,acting to force valve stem 122 into valve seat 124. When pressure issufficiently reduced within pressure lumen 204, valve stem 122 retractsproximally from valve seat 124, thereby allowing high pressure fluid inreservoir 129 and high pressure lumen 108 to extend through nozzle 126,exiting orifice 132 as jet 130. In one embodiment, not requiringadditional illustration, a spring, similar to spring 114 of FIG. 3, isdisposed within accumulator region 206, thereby acting to bias valvebody 118 in a closed, distal position. In another embodiment, fluid mustbe supplied through lower pressure lumen 204 to maintain valve stem 122against valve seat 124. In this embodiment, pressure may besubstantially reduced so as to allow high pressure flow through nozzle126.

[0028] In yet another embodiment, needle valve body 118 and block 120are cooperatively sized such that valve stem 122 is at least partiallyurged from valve seat 124 by high pressure fluid within high pressurelumen 108. In this embodiment, less pressure reduction is required toopen the valve to high pressure fluid flow. In one embodiment, negativepressure or vacuum must be applied to lower pressure lumen 204 in orderto maintain valve stem 122 in a proximal position clear of valve seat124. In another example of the invention, lower pressure lumen 204 andhigh pressure lumen 108 are both provided within separate lumens of asingle shaft. In another embodiment, lower pressure lumen 204 and highpressure lumen 108 are defined by separate, metallic, tubes. A preferredmetallic tube includes Nitinol. The lower pressure control fluid can beprovided from the catheter proximal end and can be controlled using alower pressure control valve.

[0029] Referring now to FIG. 5, another fluid jet PMR system 300 isillustrated, having a catheter 302 including a proximal region 308, adistal region 304, and a distal end 306. An inflation device such as anEndoflator 316 is illustrated including a pressure gauge 320, and ahighly diagrammatic pressure source 318. Catheter 302 includes aproximal manifold 310 having a control port 312, illustrated having anactivation wire 314 extending therethrough. Activation wire 314 may beseen to extend the length of catheter 302, terminating within distalregion 304. In various embodiments of the invention, activation wire 314may be either retracted or extended to release fluid pressure fromwithin catheter 302, thereby forcing pressurized fluid out distal end306. In one embodiment, activation wire 314 is slidably disposed withina lumen within catheter shaft 302.

[0030] Referring now to FIG. 6, distal region 304 of catheter 302 isillustrated. Catheter 302 includes a catheter tube wall 330, having ahigh pressure lumen 332 defined therein. Catheter 302 terminatesdistally with a distal valve 334, having a distal-most orifice 336therein. A valve seat 337 is illustrated having a shoulder region 338for receiving a valve stem 340. In the embodiment illustrated in FIG. 6,valve seat 337 receives valve stem 340 which prevents fluid from exitingthrough valve 334. In the illustrated embodiment, valve stem 334 is asubstantially spherical element, coupled to an activation wire 314. Inone embodiment, activation wire 314 is formed of Nitinol, and valve stem340 is integrally formed with wire 314 by heating wire 314, therebycausing the wire to melt and form a ball at the distal-most end. In apreferred embodiment, activation wire 314 has sufficient column strengthto allow valve stem 340 to be forced against valve seat 337, therebyclosing the valve. In another embodiment, not requiring separateillustration a biasing spring, similar to spring 114 of FIG. 3, isprovided within lumen 332 and can be held by a fixed block similar tothat illustrated in FIG. 3. In an embodiment having sufficient biasingmeans, activation wire 314 need only be strong enough to open valve 334,with the closing being accomplished by the biasing spring.

[0031] Catheter 302 may also be seen to have a tube wall distal region348 and a far distal region 350. In one embodiment, far distal region350 is formed of a more pliant material than distal region 348 disposedproximal of distal region 350. In particular, far distal region 350 canbe expanded under pressure so as to substantially increase the distalprofile of catheter 302. Catheter wall 330 may also include a bondingregion 342 where tube wall 330 is strongly bonded to valve 334.

[0032] Referring now to FIG. 7, catheter 302 is illustrated in anexpanded configuration. In FIG. 7, far distal region 350 has beenexpanded to have a substantially greater distal cross-sectional profilethan the more proximal distal region 348. In one embodiment, far distalregion 350 has a unexpanded length of about one-half inch (½″).Inspection of FIG. 7 indicates that distal region 348 has not expandednearly as far as distal region 350, due to the difference of materialsbetween the two regions. In one example, far distal region 350 is formedof an elastomeric substance which recovers the initial dimension uponthe reduction of pressure. In another embodiment, far distal region 350is formed of a material which undergoes plastic deformation under highpressure. As can be seen from inspection of FIG. 7, catheter far distalregion 350 can significantly expand under pressure. Catheter distalregion 350 can be forced against the heart chamber wall, there providinga better seal about distal nozzle 334 and distal orifice 336. This cansignificantly improve the seal against the heart wall and around theholes formed in the heart wall. In one embodiment, silicone rubber isincluded in the walls of far distal region 350. In another embodiment,PEBAX is used in both distal region 314 and far distal region 350, withthe far distal region having lower cross-linking PEBAX material thandistal region 314. The lower cross-linking can provide a more easilyexpanded material.

[0033] Referring now to FIG. 8, catheter 302 is shown from an end viewin an expanded state, illustrating central orifice 336 within nozzle334. Far distal region 350 may be seen to have expanded a distal profilesignificantly. By providing increased surface area for contact of thecatheter distal region against the heart wall, the seal may be improved,and the amount of fluid under pressure that will enter the myocardiumcan be increased.

[0034] Referring now to FIG. 9, a PMR catheter 400 is illustrated,having a proximal region 410, an intermediate region 406, a distalregion 412, a far distal region 404, and a distal end 402. Device 400may include differing materials of construction as discussed withrespect to FIG. 7. Device 400 includes intermediate region 406 formed ofa more pliant material, as well as far distal region 404 being formed ofa more pliant material. A more rigid material may be found in proximalregion 410, as well as distal region 412. The more pliant material maybe seen to be employed in regions 406 and 404. Catheter 400 isillustrated in an inflated position. Intermediate, inflatable portion406 can be disposed about six inches proximal of distal end 402 in oneembodiment. In one embodiment, the expandable regions are formed ofPEBAX, as are non-expandable regions, with the expandable regions havinga significantly lower degree of cross-linking. Expanded intermediateregion 406 can serve to expand a catheter until the catheter is expandedagainst the walls of a containing guide catheter. Expanded region 406can thus stabilize the distal region of the fluid jet PMR device. Withthe distal region thus stabilized, fluid being injected from distal end402 may be counteracted by the secured intermediate region. Inparticular, the reactionary force from the injecting fluid may becounteracted by the expanded balloon within the guide catheter. In thisway, higher pressures, and, in some instance, greater flow rates, may beemployed in forming the myocardial holes.

[0035] Various fluids may be employed in using the present invention. Inone embodiment, saline is used as the high pressure fluid. In anotherembodiment, saline is combined with therapeutic substances to promotehealing and/or angiogenesis within the myocardium. Examples oftherapeutic substances include small molecular drugs, proteins, genesand cells which could promote angiogenesis, protect tissues (i.e.,cardiac protection), or promote tissue regeneration. VascularEndothelial Growth Factor (VEGF) and Fibroblast Growth Factors (FGFs)are believed suitable for use with the present invention. Carriers forthe therapeutic agents of the present invention can include polymers,angiopoietins, biodegradable and biostable hydrogels, and dissolublepolymers. Adhesives suitable for binding the present invention includefibrin glues and cyanoacrylates which may also be included with thetherapeutic substance to improve the desired response. Drug injectioncatheters referred to in the remainder of the present patentapplication, and drugs similarly referenced, may include the injectionand use of the aforementioned therapeutic substances.

[0036] In one embodiment, contrast media is included with the cuttingfluid, to provide an indication under fluoroscopy of regions of theheart chamber wall that have been already visited by the fluid jet PMRtip. The contrast media can be injected into holes within the heartwall, which may show up under fluoroscopy.

[0037] In an embodiment, a high pressure fluid pressure of at leastabout 10 atmospheres is used. In some embodiments of the invention,fluid pressure is built up slowly in the distal region of the catheter,and released quickly by use of a distally disposed control valve, aspreviously discussed. In one example, a distal reservoir region, asindicated in FIGS. 3 and 4, is included to provide a substantial volumeof fluid for injecting, even though, in steady state, the high pressurelumen is not sufficiently large to maintain a high flow rate over a longtime. The fluid jet PMR fluid may thus be supplied slowly, built upunder pressure, and released quickly in jets by a control valve disposedwithin the catheter. The distal control valve can also have a largercross-section distal-most orifice than would be possible if this orificediameter required and maintained the entire length of the catheter. Thedistal control valve can also provide means for ensuring that the fluidis not injected into the heart chamber until the distal tip is properlypositioned.

[0038] Numerous advantages of the invention covered by this documenthave been set forth in the foregoing description. It will be understood,however, that this disclosure is, in many respects, only illustrative.Changes may be made in details, particularly in matters of shape, size,and arrangement of parts without exceeding the scope of the invention.The invention's scope is, of course, defined in the language in whichthe appended claims are expressed.

What is claimed is:
 1. A catheter for forming holes in the myocardium ofa heart chamber wall, said catheter having a distal region and aproximal region, said catheter comprising: an elongate tubular shafthaving a length, a first lumen therethrough, and a distal nozzle influid communication with said first lumen; a valve disposed along saidelongate shaft length for controlling fluid flow through said lumen andbeing in fluid communication with said lumen; and means for controllingsaid valve from said tubular shaft proximal region.
 2. A catheter as inclaim 1, wherein said valve has an open position and a closed position,further comprising means for biasing said valve in said closed position.3. A catheter as in claim 1, wherein said valve has an open position anda closed position, further comprising means for closing said valve fromsaid shaft proximal region.
 4. A catheter as in claim 1, wherein saidnozzle is sufficiently strong to deliver fluids at a pressure of atleast about 10 atmospheres.
 5. A catheter as in claim 1, wherein saidvalve includes a valve stem member and a valve seat member for receivingsaid valve stem member thereagainst.
 6. A catheter as in claim 1,wherein said valve includes a valve seat member having an orificetherethrough and a valve stem member for occluding said orifice.
 7. Acatheter as in claim 6, wherein said means for controlling said valveincludes an elongate control member extending from said catheterproximal region and operably coupled to said valve stem member.
 8. Acatheter as in claim 7, wherein said valve includes a spring for biasingsaid valve stem in a closed position.
 9. A catheter as in claim 1,wherein said valve includes means for controlling said valve with fluidpressure, and said catheter further includes a second lumen fortransmitting fluid pressure to said means for controlling said valvewith fluid pressure.
 10. A catheter as in claim 1, wherein said meansfor controlling said valve includes means for opening and closing saidvalve in response to varying fluid pressure.
 11. A catheter as in claim1, wherein said means for controlling said valve includes a temperaturesensitive member which changes shape in response to changingtemperature, wherein said catheter further includes at least oneelectrode for providing electrical current to said temperature sensitivemember for heating said temperature sensitive member.
 12. A catheter asin claim 11, wherein said valve includes a biasing device for biasingsaid valve in a closed position.
 13. A catheter as in claim 1, whereinsaid catheter shaft includes a shaft wall, wherein said shaft wall isformed of a first portion and a second portion, wherein said secondportion is expandable under pressure to a greater degree than said firstportion, such that said second portion expands in diameter greater thanat least 20 percent.
 14. A catheter as in claim 13, wherein said secondportion expands in diameter greater than at least about 40 percent. 15.A catheter as in claim 13, wherein said second portion is disposed nearsaid catheter distal region.
 16. A catheter as in claim 15, wherein saidsecond portion has a first, unexpanded configuration with a firstdistal-most profile, and a second, expanded configuration with a seconddistal-most profile, wherein said catheter second distal-most profile issignificantly greater than said first distal-most profile.
 17. Acatheter as in claim 16, wherein said second distal-most profile is atleast twice as large as said first distal-most profile.
 18. A catheteras in claim 17, wherein said second portion is disposed proximal of saiddistal region, such that said second portion can be disposed within aguide catheter while said distal region is disposed against said heartwall, such that said second portion expands against said guide catheterto stabilize said myocardial revascularization catheter during use. 19.A catheter for forming holes in the myocardium of a heart chamber wall,said catheter having a distal region and a proximal region, saidcatheter comprising: an elongate tubular shaft having a length, a firstlumen therethrough, and a distal nozzle in fluid communication with saidlumen; a valve disposed along said elongate shaft length for controllingfluid flow through said lumen; and a valve actuator for controlling saidvalve from said tubular shaft proximal region.
 20. A catheter as inclaim 19, wherein said valve has an open position and a closed position,further comprising a biasing device for biasing said valve in saidclosed position.
 21. A catheter as in claim 19, wherein said valve hasan open position and a closed position, wherein said valve actuatorincludes a closing device for closing said valve from said shaftproximal region.
 22. A catheter as in claim 19, wherein said nozzle issufficiently strong to deliver fluids at a pressure of at least about 10atmospheres.
 23. A catheter as in claim 19, wherein said valve includesa valve stem member and a valve seat member for receiving said valvestem member thereagainst.
 24. A catheter as in claim 19, wherein saidvalve includes a valve seat member having an orifice therethrough and avalve stem member for occluding said orifice.
 25. A catheter as in claim24, wherein said valve controller for controlling said valve includes anelongate control member extending from said catheter proximal region andoperably coupled to said valve stem member.
 26. A catheter as in claim25, wherein said valve includes a spring for biasing said valve stem ina closed position.
 27. A catheter as in claim 19, wherein said valvecontroller is pressure actuated, and said catheter further includes asecond lumen for transmitting fluid pressure to said valve forcontrolling said valve with fluid pressure.
 28. A catheter as in claim19, wherein said valve controller includes a device for opening andclosing said valve acting in response to varying fluid pressure.
 29. Acatheter as in claim 19, wherein said valve controller includes atemperature sensitive member which changes shape in response to changingtemperature, wherein said catheter further includes at least oneelectrode for providing electrical current to said temperature sensitivemember for heating said temperature sensitive member.
 30. A catheter asin claim 29, wherein said valve includes a biasing device for biasingsaid valve in a closed position.
 31. A catheter as in claim 19, whereinsaid catheter shaft includes a shaft wall, wherein said shaft wall isformed of a first portion and a second portion, wherein said secondportion is expandable under pressure to a greater degree than said firstportion, such that said second portion expands in diameter greater thanat least 20 percent under pressure.
 32. A catheter as in claim 31,wherein said second portion expands in diameter greater than at leastabout 40 percent.
 33. A catheter as in claim 31, wherein said secondportion is disposed near said distal region.
 34. A catheter as in claim33, wherein said expandable second portion has a first unexpandedconfiguration with a first distal-most profile and a second expandedconfiguration with a second distal-most profile, wherein said cathetersecond distal-most profile is significantly greater than said firstdistal-most profile.
 35. A catheter as in claim 34, wherein said seconddistal-most profile is at least twice as large as said first distal-mostprofile.
 36. A catheter as in claim 35, wherein said second portion isdisposed proximal of said distal region, such that said second portioncan be disposed within a guide catheter while said distal region isdisposed against said heart wall, such that said second portion expandsagainst said guide catheter to stabilize said myocardialrevascularization catheter during use.
 37. A method for performingmyocardial revascularization from within a heart chamber having a wall,the method comprising forming holes in the myocardium using at least onefluid jet.
 38. A method for performing myocardial revascularization asin claim 37, wherein said hole forming step includes injecting at leastone therapeutic substance into said myocardium in said forming step. 39.A method for performing myocardial revascularization as in claim 37,wherein said method includes providing a catheter having a proximalregion, a distal region, a lumen therethrough, and a distal valve influid communication with said lumen, wherein said forming step includesejecting said fluid from said distal valve.
 40. A method for performingmyocardial revascularization as in claim 39, wherein said methodincludes controlling said valve from said catheter proximal region. 41.A method for performing myocardial revascularization as in claim 39,wherein said method includes expanding said catheter distal region froma first distal profile to a second, expanded distal profile greater thansaid first distal profile, wherein said second expanded distal profileis disposed against said heart chamber wall for an improved seal againstsaid heart chamber wall.
 42. A method for performing myocardialrevascularization as in claim 39, wherein said method includes expandinga catheter intermediate region from a first diameter to a second,expanded diameter greater than said first diameter, wherein said secondexpanded diameter is disposed within a guide catheter for stabilizingsaid catheter during fluid injection.